Device for bipolar high-frequency coagulation of biological tissue

Abstract

A device for bipolar high-frequency coagulation of biological tissue between two contact faces of a coagulating instrument. The two contact faces are connected to an output of a high-frequency generator. A temperature sensor is arranged near each of the two contact faces. A circuit for evaluating the measured temperatures and/or the temperature differential controls the coagulation temperature and the shutoff of the high-frequency generator as a preselected temperature or temperature differential is exceeded. Moreover, an indicating device is provided for acoustically and/or optically indicating the temperatures on the contact faces as well as the temperature differential between the contact faces.

What is claimed is: 
     
       1. A device for bipolar high-frequency coagulation of biological tissue comprising: a coagulating pincer with a first shank defining a first contact face and a second shank defining a second contact face;   a controllable high-frequency generator;   said first shank contact fee and said second shank contact face electrically connected to said generator;   a pair of temperature sensors, one of said sensors located near said first shank contact face and the other of said sensors located near said shank contact face;   evaluation means having a controller for controlling said high-frequency generator with a first selectively preset input representing a predetermined coagulation temperature and a second input;   a first comparator connected to said temperature sensors, and having an output; and   changeover switch means having a first input connected to said output of said first comparator, a second input connected to one of said temperature sensors, a third input connected to the other of said temperature sensors, and an output connected to said second input of said controller, whereby said changeover switch means electrically connects the temperature sensor representing the highest temperature to said second input of said controller;   said evaluation means connected to said temperature sensors for evaluating the temperatures near said first and second contact faces and controlling said high-frequency generator in response to said highest temperature.   
     
     
       2. The device according to claim 1 wherein said first shank defines a first shank tip and said second shank defines a second shank tip, wherein said first and second contact faces are, respectively, located on said shank tips and said temperature sensors are embedded in said shank tips. 
     
     
       3. The device according to claim 2 wherein said temperature sensors are encased thermacouples which extend into said first and second shank tips. 
     
     
       4. The device according to claim 3 wherein each of said temperature sensors is a connection junction of an NiCrNi encased thermoelement. 
     
     
       5. The device according to claim 3 wherein said first and second shanks of said coagulating pincers comprise longitudinal grooves, said grooves originating from the inside of each of said first and second contact faces facing one another and extending up into said first and second shank tips, said encased thermocouples embedded within said grooves by hard solder. 
     
     
       6. The device according to claim 1 wherein said temperature sensors are resistance elements with a positive temperature coefficient. 
     
     
       7. The device according to claim 1 wherein said evaluation means further comprises a differential amplifier having two inputs and an output, said inputs respectively connected to said pair of temperature sensors, and a second comparator having a first input connected to said output of said differential amplifier, a second input connected to a selectively preset input representing a cutout temperature difference, and an output connected to said high frequency generator for switching off said generator when said selectively preset cutout temperature difference is exceeded. 
     
     
       8. The device according to claim 7 further comprising an acoustic indicating unit connected to said ouput of said differential amplifier.   
     
     
       9. The device according to claim 8 wherein, said indicating unit includes means for varying one of a sound frequency and loudness in response to the output from said differential amplifier and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       10. The device according to claim 7 further comprising an optical indicating unit connected to said output of said differential amplifier.   
     
     
       11. The device according to claim 10 wherein, said indicating unit includes means for varying one of a flicker frequency, brightness and color in response to the output from said differential amplifier and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       12. The device according to claim 7 further comprising an optical and acoustic indicating unit connected to said output of said differential amplifier.   
     
     
       13. The device according to claim 12 wherein, said indicating unit includes means for varying one of a sound frequency, flicker frequency, loudness, brightness and color in response to the output of said differential amplifier and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       14. The device according to claim 1 further comprising an optical indicating means connected to said temperature sensors forindicating the temperatures on said contact faces. 
     
     
       15. The device according to claim 14 wherein, said indicating means includes means for varying one of a flicker frequency, brightness and color in response to the temperatures on said contact faces and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       16. The device according to claim 1 further comprising an acoustic indicating means connected to said temperature sensors for indicating the temperatures on said contact faces. 
     
     
       17. The device according to claim 16 wherein, said indicating means includes means for varying one of a sound frequency and loudness in response to the temperatures on said contact faces and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       18. The device according to claim 1 further comprising an acoustic and optical indicating means connected to said temperature sensors for indicating the temperatures on said contact faces. 
     
     
       19. The device according to claim 18, wherein, said indicating means includes means for varying one of a sound frequency, flicker frequency, loudness, brightness and color in response to the temperature on said contact faces and wherein the variation variable is strongest in the vicinity of a preset value. 
     
     
       20. A device for bipolar high-frequency coagulation of biological tissue comprising; a coagulating pincer with a first shank defining a first contact face and a second shank defining a second contact face;   a controllable high-frequency generator;   said first shank contact face and said second shank contact face electrically connected to said generator;   a pair of temperature sensors, one of said pair of sensors located near said first shank contact face and the other of said sensors located near said second shank contact face;   a control means having a controller with a first and second input and an output, said first input connected to a selectively preset electrical signal representing a predetermined coagulation temperature, said output connected to said high-frequency generator   a first comparator connected to said temperature sensors and having an output; and   changeover switch means having a first input connected to said output of said first comparator, a second input connected to one of said temperature sensors, a third input connected to the other of said temperature sensors, and an output connected to said second input of said controller, whereby said changeover switch means electrically connects the temperature sensor representing the highest temperature to said second input of said controller;   said control means connected to said temperature sensors for evaluating the temperatures near said contact faces and controlling said high-frequency generator in response to the temperatures sensed by said sensors.   
     
     
       21. The device according to claim 20 wherein said first shank defines a first shank tip and said second shank defines a second shank tip, wherein said first and second contact faces are, respectively, located on said first and second shank tips and said temperature sensors are encased thermocouples embedded in said shank tips. 
     
     
       22. The device according to claim 20 wherein said control means comprises a differential amplifier having an input and an output, said input connected to said temperature sensors, and a second comparator having a first input connected to said output of said differential amplifier, a second input connected to a selectively preset input representing a temperature difference, and an output connected to said high-frequency generator, said control means independently switching off said generator when said selectively preset temperature difference is exceeded. 
     
     
       23. A device for bipolar high-frequency coagulation of biological tissue comprising; a coagulating pincer with a first shank defining a first contact face and a second shank defining a second contact face;   a controllable high-frequency generator;   said first shank contact face and said second shank contact face electrically connected to said generator;   a pair of temperature sensors, one of said pair of sensors located near said first shank contact face and the other of said sensors located near said second shank contact face;   control means for connecting the highest temperature of one of said first contact face and said second contact face to said generator,   means for sensing the temperature differential between said first contact face sensor and said second contact face sensor;   said control means for connecting the highest temperature contact face and said means for sensing the temperature differential coupled between said temperature sensors and said generator to control the energization of said pincer.